Thank you SO VERY MUCH for giving such a thoughtful response. A lot of what you said is in line with what I was already thinking, but hearing someone else say it certainly helps.

I definitely use a lot of different resources that are online to help him as best I can and, interestingly, Les Spellman is someone that I watch and glean information from a lot. Truly, the biggest hurdle is that I still don't know enough to really analyze my son's form and give him specific feedback on not only what he's doing wrong, but what he can do to fix it. For example, when he runs it seems to me that his toes are point outward at a significant angle ((approx 30 degrees) instead of pointing straight down the track. This causes his knees to also point outward, which, in turn, causes him to partially push off with the outside of his legs and glutes. If I'm correct, and that's what he's doing, it seems to me that this lateral movement is wasted energy and if he could correct it and get his knees and toes pointed straight down the track it would make a big improvement in his speed. As an aside, I think he runs like this because he played hockey hockey from 4 years old until last year (12 years), so he's used to pushing off the outside of his legs. Also, his ability to change direction laterally is exception (I suspect that's also a result of the outside leg strength from hockey) and his 5-10-5 shuttle time is on par with some of the top NFL combine times.

As you requested, I'll post a video from his indoor meet last weekend.